Earlier quoted context omitted.
I've glanced through the license. You are allowed to install it on as many machines as you need as long as only you use it. I can't see any limitations on what work you can do or who for. My conclusion is that as long as you have paid for it you can use it at work but cannot reclaim expenses for it or transfer it in any way.
> but cannot reclaim expenses for it How is that a valid condition (legally)? If you bought a programming book on your Kindle, Amazon would have no legal ground to prohibit your company from reimbursing you.
It's actually a valid scenario. Suppose you want to evaluate IDEA for your company but need more than 30 days. You could buy the personal edition and use it. After your evaluation is done, the company reimburses you. If you liked it, presumably your company bought a site license at the same time which you can use instead. If you didn't just stop using it.